﻿using System;

namespace AT.IBMS.Framework.Tools
{
    public static class IdentityCardTool
    {

        /// <summary>
        /// 返回身份证性别
        /// </summary>
        /// <param name="IdentityCard">身份证号</param>
        /// <returns>1为男,2为女</returns>
        public static int GetSexByIdentityCard(this Tool t, string IdentityCard)
        {
            if (string.IsNullOrEmpty(IdentityCard))
                return 0;
            string sex;
            if (IdentityCard.Length == 15)
            {
                sex = IdentityCard.Substring(IdentityCard.Length - 1, 1);
            }
            else if (IdentityCard.Length == 18)
            {
                sex = IdentityCard.Substring(IdentityCard.Length - 2, 1);
            }
            else
            {
                return 0;
            }
            if (int.Parse(sex) % 2 == 0)
                return 2;
            else
                return 1;
        }

        /// <summary>
        /// 返回身份证出生日期
        /// </summary>
        /// <param name="IdentityCard">身份证号</param>
        /// <returns></returns>
        public static string GetBirthdayByIdentityCard(this Tool t, string IdentityCard)
        {
            if (string.IsNullOrEmpty(IdentityCard))
                return null;
            string birthday;
            if (IdentityCard.Length == 15)
            {
                birthday = IdentityCard.Substring(6, 6);
            }
            else if (IdentityCard.Length == 18)
            {
                birthday = IdentityCard.Substring(6, 8);
            }
            else
            {
                return null;
            }
            return FormatDate(birthday);
        }

        /// <summary>
        /// 验证身份证是否正确
        /// </summary>
        /// <param name="IdentityCard">要验证的身份证号</param>
        /// <returns></returns>
        public static bool ValidatorIdnetityCard(this Tool t, string IdentityCard)
        {
            if (IdentityCard.Length == 18)
            {
                bool check = CheckIDCard18(IdentityCard);
                return check;
            }
            else if (IdentityCard.Length == 15)
            {
                bool check = CheckIDCard15(IdentityCard);
                return check;
            }
            else
            {
                return false;
            }
        }

        /// <summary>
        /// 验证18位身份证是否正确
        /// </summary>
        /// <param name="Id">要验证的身份证号</param>
        /// <returns></returns>
        private static bool CheckIDCard18(string Id)
        {
            long n = 0;
            if (long.TryParse(Id.Remove(17), out n) == false || n < Math.Pow(10, 16) || long.TryParse(Id.Replace('x', '0').Replace('X', '0'), out n) == false)
            {
                return false;//数字验证            
            }
            string address = "11x22x35x44x53x12x23x36x45x54x13x31x37x46x61x14x32x41x50x62x15x33x42x51x63x21x34x43x52x64x65x71x81x82x91";
            if (address.IndexOf(Id.Remove(2)) == -1)
            {
                return false;//省份验
            }
            string birth = Id.Substring(6, 8).Insert(6, "-").Insert(4, "-");
            DateTime time = new DateTime();
            if (DateTime.TryParse(birth, out time) == false)
            {
                return false;//生日验证            
            }
            string[] arrVarifyCode = ("1,0,x,9,8,7,6,5,4,3,2").Split(',');
            string[] Wi = ("7,9,10,5,8,4,2,1,6,3,7,9,10,5,8,4,2").Split(',');
            char[] Ai = Id.Remove(17).ToCharArray();
            int sum = 0;
            for (int i = 0; i < 17; i++)
            {
                sum += int.Parse(Wi[i]) * int.Parse(Ai[i].ToString());
            }
            int y = -1;
            Math.DivRem(sum, 11, out y);
            if (arrVarifyCode[y] != Id.Substring(17, 1).ToLower())
            {
                return false;//校验码验证            
            }
            return true;//符合GB11643-1999标准        
        }

        /// <summary>
        /// 验证15位身份证是否正确
        /// </summary>
        /// <param name="Id">要验证的身份证号</param>
        /// <returns></returns>
        private static bool CheckIDCard15(string Id)
        {
            long n = 0;
            if (long.TryParse(Id, out n) == false || n < Math.Pow(10, 14))
            {
                return false;//数字验证            
            }
            string address = "11x22x35x44x53x12x23x36x45x54x13x31x37x46x61x14x32x41x50x62x15x33x42x51x63x21x34x43x52x64x65x71x81x82x91";
            if (address.IndexOf(Id.Remove(2)) == -1)
            {
                return false;//省份验证            
            }
            string birth = Id.Substring(6, 6).Insert(4, "-").Insert(2, "-");
            DateTime time = new DateTime();
            if (DateTime.TryParse(birth, out time) == false)
            {
                return false;//生日验证            
            }
            return true;//符合15位身份证标准        
        }

        private static string FormatDate(string birthday)
        {
            if (string.IsNullOrEmpty(birthday))
            {
                throw new ArgumentNullException("birthday is not null");
            }
            if (birthday.Length == 6)
            {
                birthday = birthday.Insert(2, "-");
                birthday = birthday.Insert(5, "-");
            }
            else if (birthday.Length == 8)
            {
                birthday = birthday.Insert(4, "-");
                birthday = birthday.Insert(7, "-");
            }

            return birthday;
        }

    }
}
